Closure means for vacuum chambers

ABSTRACT

The present closure means, such as a gate for vacuum chambers, is movably supported in front of an opening of such a vacuum chamber on a carriage by means of flat or leaf springs which permit a movement of the gate toward and away from said opening.

United States Patent [191 Heiland Jan. 8, 1974 CLOSURE MEANS FOR VACUUM CHAMBERS 56] References Cltctl [75] Inventor: Manfred Heiland, Hahn/Pfungstadt, UNITED STATES PATENTS Germany 1,023,833 4/1912 Gaines 16/103 X [73] Assignee; Firma Carl Schenck GmbH,

Damstadt Gummy 3,386,203 6/1968 Butler er a1. 220/41 x [22] Filed: Oct. 20, 1971 Primary Examiner-Kenneth Downey 211 App]. No.. 190,801 Atmmey w G. Fasse [30] Foreign Application Priority Data 57 ABSTRACT Aug. 14, 1971 Germany P 21 40 880.0 The e e closure means such a gate vacuum chambers, is movably suppdrtedin front of an opening E 8]. "iiigd49/52/21 of such a vacuum chamber on a cam-m by means of [58 Field of Search 49/147, 208, 209, flat leaf spmgs whlch Perm" a "memem gate toward and away from said opening.

5 Claims, 2 Drawing Figures 1 CLOSURE MEANS FOR VACUUM CHAMBERS BACKGROUND OF THE INVENTION The present invention relates to closure means, especially gate type closure means for vacuum chambers which have an opening extending in a vertical plane. The present closure gate is especially suitable in connection with vacuum chambers or vessels for containing balancing and/or centrifugal testing equipment.

Balancing and centrifugal, testing equipment, for example, for bladed rotors are normally placed into large cylindrical chambers arranged in a horizontal position and having a rigidly closed end wall as well as a closable end wall. For this purpose a so called gate is provided which, in its open condition, uncovers the entire chamber cross-sectional area in order to facilitate placing the testing equipment into the chamber as well as to remove it again.

Such a gate may be connected to the cylinder housing or chamber by means of hinges attached to said chamber. However, especially in connection with rather large centrifugal testing equipment, the gate has been suspended from displaceable means arranged above the chamber. In such an arrangement, the gate is displaceable in a direction extending perpendicularly to the longitudinal or central axis of the cylindrical vacuum chamber. Such displacement cross-wise so to speak relative to the longitudinal chamber axis is necessary because these large chambers are charged or their content is discharged over rail tracks having hinged rail pieces which open up within the range of the gate.

It has been found that the suspended arrangement of the gate has certain disadvantages, especially since it requires a substantial investment either in the construction of the ceiling from which the gate is suspended or in the provision of special supporting structures and the foundation required for such structures. As a result, these additional structural requirements substantially increase the costs of the complete testing facility.

OBJECTS OF THE INVENTION In view of the foregoing, it is the aim of the invention to achieve the following object s, singly or'in combination:

to overcome the drawbacks of the prior art as outlined abovej to provide a gate supporting structure for the gate of a vacuum chamber having an opening extending in a vertical plane, whereby supporting structural means extending above the chamber are to beavoided;

to provide supporting means for said gate which have a sufficient flexibility to permit movement of the gate toward and away from said vertically extending opening of the chamber;

to assure that the gate may be strongly pressed against the chamber opening so that the chamber may be sealed in a vacuum tight manner;

to reduce the closure and gate moving means to a minimum;

to facilitate the lateral displacement of the gate relative to said opening and in parallel thereto; and

to avoid or at least reduce to a minimum any vibrations to which the gate might be subject.

SUMMARY OF THE INVENTION The above objects have been achieved according to the invention in a gate structure for closing the vertical opening of a vacuum chamber by supporting the gate on a carriage by means of flat or'leaf springs. The resonant or natural frequency of the spring mass system comprising the gate and said supporting leaf springs is preferably selected in such a manner that said frequency is rather low, preferably close to zero.

In a preferred embodiment, according to the invention, the gate is supported on a carriage by two leaf spring systems arranged symmetrically relative to a vertical center line of the gate. In a preferred embodiment the carriage is moveable on rails which suitably should extend in the direction of the plane defining the opening of the chamber.

BRIEF FIGURE DESCRIPTION DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS:

In the illustrated embodiment the gale 1, according to the inventionhas a circular shape. However, the invention is not limited to such shape. For example, the

gate could also have a square or rectangular shape. The

gate 1 is supported on carriage means land 3 by means of flat or leaf springs 4,5, 6, and 7 which are arranged in the form of two spring systems 4 and 5 as well as 6 and 7 respectively."Ihe spring systems in turn are arranged symmetrically relative to a vertical center line of the gate and in such, a manner that the leaf springs 4 to 7 extend in parallel to the plane defining the opening in the vacuum chamber 15. The opening of the chamber may be surrounded by a rim or edge for cooperation with the surface "of the gate 1 as best seen in FIG. 2.

The carriage means 2 and 3 are, for example, supported on rails 13, 1 4 and are displaceable in a direction parallel to theplane defined by the gate 1 or. by the plane of the opening of thechamber 15. Although it is possible to use but one leaf spring in each system, it is preferable for stabilitys sake to use two springs in each system whereby the springs of each system are arranged with a spacing therebetween as best seen in FIG. 2

The spring rate or stiffness of the leaf springs 4, 5, 6, and 7 is selected in such a manner that the spring mass system .comprising said leaf springs and the mass of the gate have a very low natural or resonant frequency. Thus, it is easily possible to move the relatively heavy gate sufficiently in the direction toward and away from the chamber opening, whereby it is possible to press the gate tightly against the opening of the vacuum chamber and thus seal it in a vacuum tight manner. Thus, it is an advantage of the invention that no special mechanisms for moving the gate in the longitudinal direction of the chamber 15 are necessary and the closure may be accomplished due to the fact that .tie chamber is subjected to reduced pressure which has the further advantage that no special closure or rather locking means are required.

of the chamber independent of the established vacuum,

gate 1 may be provided with additional means for pressing the gate against the chamber opening. For this purpose, there may be provided studs 9, extending laterally from the gate 1 and fitting into respective eylets ll, 12 extending laterally from the chamber 15. Normally, the carriage means 2 and 3 will be movable away from the position opposite the chamber opening in but one direction, for example, to the right as seen in FIG. 1. Therefore, the eyelet 11 may be arranged in a fixed position whereas the eyelet 12 would be journaled to a respective stud for tilting it between an open and a closing position. Thus, the stud 9 would move into the eyelet 11 as the gate 1 is shifted leftwardly. Thereafter, the tiltable or otherwise movable eyelet 12 is brought to engage the stud 10. The eyelets 11 and 12 may, for example, beconnected to hydraulic piston cylinder arrangements and through these arrangements to the vacuum chamber 15, whereby the gate is rigidly pressed against the opening of the chamber by means of said piston cylinder arrangements not shown.

The movability or shiftability of the gate 1 parallel to the plane defined by the opening of the chamber 15 simplifies substantially the vacuum tight closing of the chamber because it eliminates the heavy super structures heretofore required. Another advantage of the arrangement as taught by the present invention is seen in that the lateral displacement of the gate, as compared to a displacement in the longitudinal direction of the central chamber axis, substantially eliminates the possibility of exciting the gate structure to oscillate.

In view of the foregoing, it will be appreciated that the device for supporting and moving the gate according to the invention is substantially simplified especially the super structure has been eliminated and the ceiling or roof construction of the building for the testing facilities need not be strengthened in any particular way since the invention has eliminated suspending the gate 1 from the ceiling. Another advantage of these features is seen in that the location of the chamber itself or a subsequent relocation of the chamber is substantially simplified and the location of the chamber may be selected more freely and with less .investment.

Although the invention has been described with reference to specific example embodiments, it is to be understood, that it is intended to cover any modification and equivalent within the scope of the appended claims.

What is claimed is:

l. A closure means for a vacuum chamber having wall means defining an opening, a gate plate, fiat leaf spring means having plane surfaces, means for connecting one end of the leaf spring means to the gate plate at the bottom edge thereof so that said plane surfaces extend in parallel to a plane defined bysaid gate plate, means for movably supporting the opposite end of said leaf spring means vertically below said gate plate, said gate plate and said leaf spring means forming a spring mass system permitting the movement of the gate plate in a direction extending substantially perpendicularly to a plane defined by said opening, said spring mass system having a resonance frequency in said direction which resonance frequency is slightly above zero.

2. The closure means according to claim 1, wherein said leaf spring means comprise two pairs of leaf springs, said supporting means comprising two carriage means, each of said carriage means supporting one pair of leaf springs, and rail means extending in parallel to said plane defined by said opening whereby said carriage means are movable in a direction extending perpendicularly to said first mentioned direction.

- 3. The closure means according to claim 1, wherein said plane defined by said opening extends vertically and wherein said leaf spring means comprise two leaf spring systems arranged-symmetrically relative to a vertical center line of said gate plate.

4. The closure means according to claim 1, further comprising means for-interconnecting the gate plate and the chamber for tightly pressing the gate plate against the opening of the chamber in the direction of the longitudinal chamber axis.

5. A closure means for a vacuum chamber having wall means defining an opening, a gate plate, leaf spring means, means for connecting one end of the leaf spring means to the gate plate, means for supporting the opposite end of said leaf spring means, said gate plate and said leaf spring means forming a spring mass system permitting the movement of the gate plate in a direction'extending substantially perpendicularly to a plane defined by said opening, said spring mass system having a resonance frequency in said direction which resonance frequency is slightly above zero, wherein said leaf spring means comprise at least two leaf springs extending in parallel to said opening, said supporting means comprising carriage means for supporting said two leaf springs which in turn support the door at the bottom thereof, and rail means extending in parallel to said plane defined by said opening whereby said carriage means are movable in a direction extending perpendicularly to said first mentioned direction, said opening plane extending vertically, and wherein said two leaf springs are arranged symmetrically relative to the vertical center line of said gate plate.

a: a: a: s: 

1. A closure means for a vacuum chamber having wall means defining an opening, a gate plate, flat leaf spring means having plane surfaces, means for connecting one end of the leaf spring means to the gate plate at the bottom edge thereof so that said plane surfaces extend in parallel to a plane defined by said gate plate, means for movably supporting the opposite end of said leaf spring means vertically below said gate plate, said gate plate and said leaf spring means forming a spring mass system permitting the movement of the gate plate in a direction extending substantially perpendicularly to a plane defined by said opening, said spring mass system having a resonance frequency in said direction which resonance frequency is slightly above zero.
 2. The closure means according to claim 1, wherein said leaf spring means comprise two pairs of leaf springs, said supporting means comprising two carriage means, each of said carriage means supporting one pair of leaf springs, and rail means extending in parallel to said plane defined by said opening whereby said carriage means are movable in a direction extending perpendicularly to said first mentioned direction.
 3. The closure means according to claim 1, wherein said plane defined by said opening extends vertically and wherein said leaf spring means comprise two leaf spring systems arranged symmetrically relative to a vertical center line of said gate plate.
 4. The closure means according to claim 1, further comprising means for interconnecting the gate plate and the chamber for tightly pressing the gate plate against the opening of the chamber in the direction of the longitudinal chamber axis.
 5. A closure means for a vacuum chamber having wall means defining an opening, a gate plate, leaf spring means, means for connecting one end of the leaf spring means to the gate plate, means for supporting the opposite end of said leaf spring means, said gate plate and said leaf spring means forming a spring mass system permitting the movement of the gate plate in a direction extending substantially perpendicularly to a plane defined by said opening, said spring mass system having a resonance frequency in said direction which resonance frequency is slightly above zero, wherein said leaf spring means comprise at least two leaf springs extending in parallel to said openIng, said supporting means comprising carriage means for supporting said two leaf springs which in turn support the door at the bottom thereof, and rail means extending in parallel to said plane defined by said opening whereby said carriage means are movable in a direction extending perpendicularly to said first mentioned direction, said opening plane extending vertically, and wherein said two leaf springs are arranged symmetrically relative to the vertical center line of said gate plate. 